Technical Field
The present disclosure relates to a torque converter, and particularly to a torque converter equipped with a lock-up device configured to transmit a torque from a front cover to a transmission-side member.
Background Information
Torque converters are often equipped with a lock-up device for directly transmitting a torque from a front cover to a turbine. For example, Japan Laid-open Patent Application Publication No. 2012-237441 describes a lock-up device including a clutch portion and a damper mechanism. The clutch portion is disposed between the front cover and the turbine. The damper mechanism is configured to transmit the torque from the clutch portion to the turbine and absorb and attenuate torsional vibration.
The damper mechanism includes an input plate, an output plate, a plurality of torsion springs and an intermediate member. The input plate is a member to which the torque is inputted from the clutch portion. The output plate is connected to the turbine. The intermediate member holds the plurality of torsion springs, and is configured to be rotatable relatively to the input plate and the output plate.
In the torque converter equipped with the lock-up device described in Japan Laid-open Patent Application Publication No. 2012-237441, the plurality of torsion springs and the intermediate member are not fixed to an output-side member, albeit the output plate is connected to the turbine. Hence, an input plate support member is fixed to a turbine hub, and radial positioning of a damper mechanism including the plurality of torsion springs and the intermediate member is done by the input plate support member. In such a well-known construction, increase in number of components is inevitable and hinders reduction in manufacturing cost. Additionally, the well-known construction results in increase in imbalance amount of a rotor including the damper mechanism and the turbine.